For Question (Init; Cond; Incre)

[Tran-Gate 0]

// Reverse case using array indexing. #include <iostream>#include <cctype>																																													  using namespace std;																																													  int main(){																																													  	 int i; char str[80] = "This Is A Test";																																													  	 cout << "Original string: " << str << "\n";	 for(i = 0; str[i]; i++) { 		  if(isupper(str[i])) str[i] = tolower(str[i]); 		  else if(islower(str[i])) str[i] = toupper(str[i]);	 } cout << "Inverted-case string: " << str;																																													  	 return 0;																																							  }

In the for statement, how is the condition str?

I am confused!!

 

Thanks in advance!!

[Nabb 0]

I don't know C++ specifically, but I'd assume that:

str returns the i^th position in the string of str

str returns undefined for anything after 'This Is A Test'

undefined evaluates to false (i.e. breaks the loop), while any character (e.g. "i", "A") evaluates to true.

Edited October 17, 2008 by Nabb (see edit history)